2 package Class::MOP::Method::Constructor;
8 use Scalar::Util 'blessed', 'weaken';
11 our $VERSION = '1.11';
12 $VERSION = eval $VERSION;
13 our $AUTHORITY = 'cpan:STEVAN';
15 use base 'Class::MOP::Method::Inlined';
21 (blessed $options{metaclass} && $options{metaclass}->isa('Class::MOP::Class'))
22 || confess "You must pass a metaclass instance if you want to inline"
23 if $options{is_inline};
25 ($options{package_name} && $options{name})
26 || confess "You must supply the package_name and name parameters $Class::MOP::Method::UPGRADE_ERROR_TEXT";
28 my $self = $class->_new(\%options);
30 # we don't want this creating
31 # a cycle in the code, if not
33 weaken($self->{'associated_metaclass'});
35 $self->_initialize_body;
43 return Class::MOP::Class->initialize($class)->new_object(@_)
44 if $class ne __PACKAGE__;
46 my $params = @_ == 1 ? $_[0] : {@_};
49 # inherited from Class::MOP::Method
50 body => $params->{body},
51 # associated_metaclass => $params->{associated_metaclass}, # overriden
52 package_name => $params->{package_name},
53 name => $params->{name},
54 original_method => $params->{original_method},
56 # inherited from Class::MOP::Generated
57 is_inline => $params->{is_inline} || 0,
58 definition_context => $params->{definition_context},
60 # inherited from Class::MOP::Inlined
61 _expected_method_class => $params->{_expected_method_class},
63 # defined in this subclass
64 options => $params->{options} || {},
65 associated_metaclass => $params->{metaclass},
71 sub options { (shift)->{'options'} }
72 sub associated_metaclass { (shift)->{'associated_metaclass'} }
78 $self->{'attributes'} ||= [ $self->associated_metaclass->get_all_attributes ]
83 sub _initialize_body {
85 my $method_name = '_generate_constructor_method';
87 $method_name .= '_inline' if $self->is_inline;
89 $self->{'body'} = $self->$method_name;
92 sub _generate_constructor_method {
93 return sub { Class::MOP::Class->initialize(shift)->new_object(@_) }
96 sub _eval_environment {
98 my $defaults = [map { $_->default } @{ $self->_attributes }];
100 '$defaults' => \$defaults,
104 sub _generate_constructor_method_inline {
107 my $meta = $self->associated_metaclass;
112 'my $class = shift;',
113 'return Class::MOP::Class->initialize($class)->new_object(@_)',
114 'if $class ne \'' . $meta->name . '\';',
115 'my $params = @_ == 1 ? $_[0] : {@_};',
116 'my $instance = ' . $meta->inline_create_instance('$class') . ';',
117 (map { $self->_generate_slot_initializer($_, $idx++) }
118 @{ $self->_attributes }),
119 $self->_preserve_weak_metaclasses,
124 warn join("\n", @source) if $self->options->{debug};
127 $self->_compile_code(\@source);
130 my $source = join("\n", @source);
131 confess "Could not eval the constructor :\n\n$source\n\nbecause :\n\n$_";
137 sub _generate_slot_initializer {
139 my ($attr, $idx) = @_;
141 my $default = $self->_generate_default_value($attr, $idx);
143 if (defined(my $init_arg = $attr->init_arg)) {
145 'if (exists $params->{\'' . $init_arg . '\'}) {',
146 $attr->_inline_set_value(
147 '$instance', '$params->{\'' . $init_arg . '\'}'
151 if (defined $default) {
154 $attr->_inline_set_value('$instance', $default),
160 elsif (defined $default) {
161 return $attr->_inline_set_value('$instance', $default);
168 sub _preserve_weak_metaclasses {
170 my $meta = $self->associated_metaclass;
171 if (Class::MOP::metaclass_is_weak($meta->name)) {
173 $meta->_inline_set_mop_slot(
174 '$instance', 'Class::MOP::class_of($class)'
183 sub _generate_default_value {
185 my ($attr, $index) = @_;
187 if ($attr->has_default) {
189 # default values can either be CODE refs
190 # in which case we need to call them. Or
191 # they can be scalars (strings/numbers)
192 # in which case we can just deal with them
193 # in the code we eval.
194 if ($attr->is_default_a_coderef) {
195 return '$defaults->[' . $index . ']->($instance)';
198 return '$defaults->[' . $index . ']';
201 elsif ($attr->has_builder) {
202 return '$instance->' . $attr->builder;
217 Class::MOP::Method::Constructor - Method Meta Object for constructors
221 use Class::MOP::Method::Constructor;
223 my $constructor = Class::MOP::Method::Constructor->new(
224 metaclass => $metaclass,
226 debug => 1, # this is all for now
230 # calling the constructor ...
231 $constructor->body->execute($metaclass->name, %params);
235 This is a subclass of C<Class::MOP::Method> which generates
242 =item B<< Class::MOP::Method::Constructor->new(%options) >>
244 This creates a new constructor object. It accepts a hash reference of
251 This should be a L<Class::MOP::Class> object. It is required.
255 The method name (without a package name). This is required.
259 The package name for the method. This is required.
263 This indicates whether or not the constructor should be inlined. This
268 =item B<< $metamethod->is_inline >>
270 Returns a boolean indicating whether or not the constructor is
273 =item B<< $metamethod->associated_metaclass >>
275 This returns the L<Class::MOP::Class> object for the method.
281 Stevan Little E<lt>stevan@iinteractive.comE<gt>
283 =head1 COPYRIGHT AND LICENSE
285 Copyright 2006-2010 by Infinity Interactive, Inc.
287 L<http://www.iinteractive.com>
289 This library is free software; you can redistribute it and/or modify
290 it under the same terms as Perl itself.